After a long time away, I have decided to return to CFS2, and I want to modify some of the existing airfields. The trouble is, I cannot seem to locate where they are stored. I have located the coastlines and roads/rivers, but not the airfields.

The only part of the default airfields stored in BGL files are the runways (scenedbrunwayssceneryallrunways.bgl)All the buildings, trees and other objects are part of the Global Scenery Layer (GSL). This is what makes them crashable and destroyable.You can add new scenery to the airfield locations using the normal FS scenery design methods but you can`t do much about the existing objects.

Thanks, I had feared that they were stored in the GSL. Looks like I will have to live with the existing airfields as is.